Two 1950s-era pipelines once used to deliver fuel to the since-shuttered Morro Bay Power Plant will be dug up and removed by the end of the year as part of the plant’s ongoing decommissioning, according to its owner.
The roughly 5,700-foot-long pipes, which travel under sand dunes and about three-quarters of a mile of coastal waters, were last used in 1990.
On Tuesday, the plant’s owner, Dynegy Inc., received environmental approval and a lease for the excavation project from the State Lands Commission, the first in a series of local, state and federal governmental agencies that need to weigh in.
Dynegy spokesman David Byford said Wednesday that the company expects to have all permits in place and begin dismantling the pipelines by the end of 2018.
The State Lands Commission lease approved Tuesday expires in 2023.
Installed by PG&E in 1954, the pipelines — one 24 inches in diameter and the other 16 — were used to offload tanker ships supplying fuel oil to the power plant for its electrical power generation.
The pipelines were declared non-operational by state and federal officials in 1997, and the plant generated its power from natural gas until its closure in 2014.
The pipelines originate just inside the western boundary of the plant property and extend northwest, under the coastal sand dunes, and terminate about 3,740 feet off the coast in roughly 54 feet of water, according to the company’s proposal. The terminals of the pipes are connected via a series of pipe spools and cargo hoses that will also be removed.
All mooring components were removed in 1994, and a buoy left behind marking the pipeline terminals went missing in 2011 and was never replaced, according to the report.
The company proposes excavating and removing the pipelines in the offshore zone beginning at the end terminals and working toward the shore. In the surf zone, the company plans to employ dynamic pipe ramming using a pneumatically powered ram to push or pull the pipes through the ground.
Morro Bay Harbor Director Eric Endersby said Wednesday that Dynegy began the permitting process for the project approximately five years ago and has been keeping the city updated on progress.
In its report, Lands Commission staff found the project would not have significant environmental impacts, and a representative for the Northern Chumash Tribal Council reportedly told staff the project’s engineering and review seemed adequate. Another requested the presence of a Northern Chumash representative and an archaeologist during the excavation.
Endersby said Dynegy previously cleaned out the interiors of the pipes to ensure they no longer contained oil or other hazardous substances.
He added that the physical work wouldn’t likely take more than two weeks, and he didn’t expect it to impact traffic in the area.
The project still requires permits from the city of Morro Bay as well as approval from the SLO County Air Pollution Control Board, the Central Coast Regional Water Quality Control Board, the State Historic Preservation Office, the U.S. Army Corps of Engineers, the U.S. Fish and Wildlife Service, the National Marines Fisheries Service and the U.S. Coast Guard.
Though the power plant continues through the decommissioning process, the ultimate fate of the 90-acre property remains unknown. In November, Dynegy announced that it had been sold to Texas-based Vistra Energy in a $1.7 billion merger, though both the company and the city have said they do not yet know how the sale may affect the future of the property.
The plant is privately owned, but the city has some influence over the property’s eventual use.